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Published on: January 24, 2013
Circadian rhythms in the vegetative state
T A Bekinschtein1, D A Golombek, S H Simonetta
1Institute of Cognitive Neurology, Buenos Aires, Argentina. tristan.bekinschtein@mrc-cbu.cam.ac.uk
Objective:
To evaluate whether vegetative state patients maintain circadian rhythms.
Research Design:
An observational study of five single cases.
Methods And Procedures:
Five chronic vegetative state patients underwent clinical and neurological evaluations and 2-week continuous temperature measurements.
Main Outcomes And Results:
The two patients with traumatic brain injury showed well-formed circadian temperature rhythms and had more reflexive behaviours and relatively low cortical and sub-cortical atrophy, whereas the three patients from anoxic-hypoxic origin demonstrated no cycles or rhythmic behaviour.
Conclusions:
The presence of periods of wakefulness does not imply preserved sleep-wake cycling capacity, nor preserved circadian rhythms and it should not be taken as a distinguishing feature for the definition of the vegetative state.
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